Controlling means for gramophones



C. A.-'F|SK. CONTROLLING MEANS FOR PHONOGRAPHS. APPLICATION FILED JULY 1; 1919.

Patented Oct. 5, 1920..

hreh/ar (bar/es H. 58/? UNITED STATES PATENT OFFICE.

CHARLEs A. FISK, 0F ABBOTSFORD, QUEBEC, CANADA.

CONTROLLING MEANS FOR GRAMOPHONES.

Specification of Letters Patent.

Patented Oct. 5, 1920.

Application filed July 1, ,1919. serial No. 307,961.

subject of the King of Great Britain and resident of Abbotsford, in the Province of Quebec and Dominion of Canada, have invented certain new and useful Improvements in Controlling Means for Gramophones, of which the following is a full, clear, and exact description.

This invention relates to improvements in means for controlling or regulating the tone and volume of sound produced by gramophones, and the object ofthe invention is to provide a simple, inexpensive, durable and easily adjusted means by which the sound produced by a gramophone may be regulated as to tone and volume.

The device consists briefly of a horn which may be built into the casing of a gramo-' phone or otherwise suitably located having separate= sounding boxes surrounding it. The tone arm of the gramophone leads into the horn and is provided with an adjustable diaphragm. Various sound regulating means may be mountedin the horn.

In the drawings which illustrate the invention;' I

Figure 1 is a vertical, longitudinal, sectional view of the device.

Fig. 2 is a front elevation.

Referring more particularly to the drawings, 11 designates the horn of a gramo-' phone which may be located within the easing 12 or otherwise suitably disposed. Thls may,;for convenience, be rectangular oss section asshown in Fig. 2 and is mrably constructed of thin sheets of *mod which will vibrate to a limited extent. each of the foursides of the home sound box 13 is provided, constructed of thin sheets of wood or othersuitable material. These sound boxes have substantially the same taper as the horn and are arranged with their small ends adjacent the small end of the horn. Both ends of the horn are open, while only the large ends of the sound boxes are open.

The tone arm 14 of the gramophone is connected to a conduit 15 which passes through one of the sound boxes into a slightly flaring mouth-piece 16, located within the horn adjacent the small end thereof. The lower end of this mouth-piece is eccentrically connected to a substantially circularly inclined soundingboard. 17 The more elevated'a'nd longer end of thissoundvided. This diaphragm is mounted -in a trunnioned frame "19 supported by vertically ad ustable telescopic posts 20. The upper ends of these posts 20 may, if desired, be

mounted in guides 21 so that the diaphragm may be moved toward or away from the mouth of the horn as well as toward or away form the .sounding board and angularly about its own axis.

In the small end of the horn a suitably shaped reflector 22 is adjustably mountedso that it may be moved toward or away from the large end of the horn.

A suitable distance in front of'the sounding board 17 and diaphragm 18 a plurality of diaphragms 23 may be mounted in the horn. The lowermost of these diaphragms is preferably the largest in diameter and the uppermost diaphragm the smallest in diameter, the intermediatediaphragms being of intermediate sizes. may be mounted by means of small studs 24 or the like, so as to be spaced away from the horn.

The operation of the device is extremely simple. Sound waves pass from the tone arm through the conduit 15 and mouth-piece 16 onto the diaphragm 18 from which they are deflected to the sounding board 17. From the sounding board the waves are deflected either to the lowermost diaphragm 23 or to the bottomwall of the horn or both. The waves are then deflected back and forth between the top and bottom of the horn until they escape at the large end thereof. This deflection back and forth of the sound waves produces amplification of the sound. In addition there is further amplification caused by vibration of the horn walls setting These diaphragms and tone are regulated by means of the diaphragm 18 which can be raised or lowered, moved backward or forward, or rocked about its trunnions so as to regulate the number and frequency of deflections within aniyI volume. ormally, the diaphragm may be v and volume.

set to deflect sound waves toward the mouth of the horn but if desired it may be made to deflect the sound waves toward the de- I fiector 22. In ordinary use the reflector serves to throw the sound waves forwardly to the mouth of the horn in much the-same manner that light is projected by a con.- densingreflector. Ordinarily, the tone is regulated by the distance between the diaphragm 18' and sounding board 17 and the volume-by the inclination of the diaphragm but it will be understood that each adjustment effects, to a certain extent, both tone It has been discovered that, by means of this apparatus, a gramophone may, as it were, be tuned to the room in which it is to beused, thus producing the desired result to the maximum degree in all circumstances. The forward and rearward adjustment bf the diaphragm will assist greatly in this tuning of the machine to the room.

Having thus described my invention, what I claim is 1. In a device of the class described, a horn, a sound conduit opening into the side of the horn, a flaring mouth-piece on said conduit within the horn, a sounding board carried by said mouth-piece and, a diaphragm below the sounding board. 2. A device according to claim 1, in which the sounding board is arranged eccentrically with respect to the mouth-piece' 3. A de ice according to claim 1, in which the sounding board is inclined with respectto the axis of the horn.

4. A device according to claim 1, in which the sounding board is arranged eccentrically with .respect to the mouth-piece and is inclined with respect tothe axes of the horn and mouth-piece, the sounding board being more remote from the horn axis at the large end than at the small end.

.adiameter thereof normal to the horn axis.

7. A device according to claim 1, in which the diaphragm is mounted for adjustment toward and away fro-m thesounding board and toward and away from the mouth of the horn.

8. A device according to claim 1, in which the diaphragm is positioned to deflect sound waves emerging from the mouth-piece onto the sounding board.

conduit within the horn, a diaphragm in the path of the conduit opposing said sounding board, and a series of additional diaphragms spaced around the inner wall of the horn between the forward end thereof and said first mentioned diaphragm.

11. In a device of the class described, a

horn having a reflector adju'stably mounted in the rear end thereof.

12. In a device of the class described, a

born, a conduit extending into the horn from horn adapted to codperate with said diaphragm in deflecting the sound waves toward the forward end of the horn.

at i

, In witness whereof, I have hereunto set m hand.

y CHARLES A. FISK. v 

